Color photographic images utilizing ureido indazolone couplers



United States Patent Office 3,486,894 Patented Dec. 30, 1969 US. Cl. 9656.5 4 Claims ABSTRACT OF THE DISCLOSURE Process for obtaining color photographic images having an improved light-stability, by means of ureido indazolone couplers and photographic material obtained thereby. Also photographic processing solutions containing ureido indazolone couplers.

The present invention refers to a process for producing color photographic images by chromogenic development of a photosensitive material in the presence of color formers called couplers of the indazolone class.

It is known that the color photography with the subtractive process is generally carried out by arranging on a support three layers of silver halide photographic emulsion, respectively sensitized to blue, green and red lights, and respectively containing couplers which, during the chromogenic development of the exposed element, react with the oxidation product of a p-phenylene diamine derivative to give yellow, magenta and cyan dyes. For each of these dyes a strong absorption in one of the three regions in which the visible spectrum is conventionally divided and a strong transmission in the two remaining regions is required. These spectral requirements reduce considerably the chemical classes available for obtaining photographic couplers.

Generally, use is made of acetanilides to obtain yellowcouplers, pyrazolones or indazolone's to obtain magentacouplers, and 1-oxy-2-naphthamides to obtain cyan-couplers. The magenta dyes, obtained during the chromogenic development, from pyrazolone couplers, have the disadvantage of having an undesired secondary absorption peak in the blue spectral region, and this is very detrimental to color purity.

Italian Patent No. 464,564 suggests the use of indazolone derivatives as magenta couplers. By chromogenic development these couplers produce dyes having favorable spectral properties, both because of the absence of undesired absorption peaks in irrelevant spectrum regions and because of a characteristic, peculiar shape of the curve in the vicinity of the main absorption peak. However, these dyes have a serious drawback, namely poor stability in the light, which shortcoming greatly reduces the possibility of their practical use.

Now, it has been found that ureido indazolone couplers of the general formula wherein R stands for H, alkyl, aryl or a heterocyclic radical, which may contain one or more substituents to make the molecule of the coupler anti-diffusing and, if desired, alkali-soluble in accordance with the known requirements for the use of the products in color photographic processes, couples with a usual chromogenic developer of the substituted p-phenylene diamine type to produce magenta dyes which, in addition to the abovementioned desirable absorption characteristics, a high light stability, making the reliable use thereof possible in the color photography.

Merely by way of illustration and not for limitation, the following examples of ureido indazolone couplers are hereinbelow set forth:

@NH-C O-NH /NH NH 1 O 0 NHS O QNH-C O-NH I NE NH C O -C17Ha 5 which were prepared as follows:

A. PREPARATION OF S-PHENYLUREIDO- INDAZOLONE (COMPOUND 1) (a) Preparation of 2-tosyl-5-nitro-indazolone 179.14 g. (1 mol) of 5-nitro-indazolone were dissolved in 1880 ml. of dry pyridine in a flask provided with reflux condenser and stirrer. To the solution thus obtained, 190.7 g. (1 mol) of p-toluene sulfochloride were slowly added. The temperature was brought at C. and the mass was left standing for 1 hour. The solution was poured into ice water and hydrochloric acid. 306 g. of product were obtained. M.P.: 178-180 C.

This product was crystallized from propanol (3300 ml.) Yield: 280 g. of 2-tosyl-5-nitro-indazolone. M.P.: 180-l83 C. Yield: 84-85%.

(b) Preparation of 2-tosyl-5-amino-indazolone 20 g. of 2-tosyl-5-nitro-indazolone (6/100 mol) were dissolved in 1000 ml. of ethanol, added with palladiated carbon (Engelhard Industries) and subjected to the action of hydrogen at ambient pressure and temperature. After completion of the reduction the suspension was filtered and the filtrate evaporated off. 13 g. of product were obtained. M.P.: 161-162 C.

This product was crystallized from methanol. Yield: 0.5 g. M.P.: 163-164 C. Yield: 35% of 2-tosyl-5- amino-indazolone. NH content =99.8%.

(c) Preparation of 2-tosyl-5-phenylureido-indazolone 18.1 g. of 2-tosyl-5-amino-indazolone (6/100 mol) were placed in a necked flask provided with reflux condenser, stirrer and dropping funnel, with 360 ml. of dry dioxane. The mixture was refluxed and to the solution 7.15 g. (6/ 100 mol) of phenyl isocyanate dissolved in 40 ml. of dry dioxane were added dropwise. The whole was refluxed during 1 hour, then poured into ice water and hydrochloric acid. 24 g. of material were obtained. M.P.: 171-172 C. (softens at 161 C.).

The material was suspended in dilute hydrochoric acid and washed plentifully with water.

23 g. of product were obtained. M.P.: 171-172 C. Yield: -91% of 2-tosyl-5-phenylureido indazolone.

(d) Preparation of 5-phenylureidoindazolone (Compound 1) 5 g. (1.161/ mol) of 2-tosyl-S-phenylureido-indazolone were slowly added to 20 ml. of 96% sulfuric acid, d a =1.84, in a beaker provided with stirrer. The whole was left under stirring during 1 hour. The solution thus obtained was poured on 400 g. of ice. The precipitate was filtered, washed plentifully with water, dried and suspended in hot-ethanol. 1.5 g. of product were obtained. M.P.: 270-275 C. Yield: 47-48% of S-phenylureidoindazolone.

B. PREPARATION OF 4' 3" STEAROYL- AMINO 5" CARBOXY) ANILINO SULFO- NYL] PHENYLUREIDO INDAZOLONE (COM- POUND 2 (a) Preparation of 2-tosyl-5-[4-(3-stearoylamino-5"- car-boxy) -anilino-sulfonyl] -phenylureido-indazolone 12.12 g. (4/100 mol) of 2-tosyl-S-amino-indazolone were placed in a necked flask provided with stirrer, reflux condenser and dropping funnel, with 180 ml. of dry dioxane. Thereafter 8.68 g. (4/100 mol) of p-chlorosulfophenyl isocyanate dissolved in 30 ml. of dry dioxane were added at the boil. The solution thus obtained was refluxed for 1 hour. In another flask, 15.05 g. (3.6/100 mol) of 3-amino-5-stearoylamino-benzoic acid and 6.4 g. (4/ 100 mol) of dry pyridine and 150 ml. of dry dioxane were placed. The whole was refluxed and, to the boiling solution, the solution previously prepared was added. After refluxing for 1 hour, the solution was poured in ice water and hydrochloric acid. 32 g. of raw product were obtained. M.P.: 175-179 C. (softens at 160 C.). This material was crystallized from acetonitrile. 18 g. of product were recovered. M.P.: 180-184 C. Yield: 49-50%.

(b) Preparation of 5 [4' (3" stearoylamino 5" carboxy) anilino sulfonyl] phenylureido indazolone (Compound 2) 18 g. (2/100 mol) of tosyl-derivative were slowly added to 320 ml. of 96% sulfuric acid, d u =1.84, cooled to 8 C. The whole was left under stirring until complete solution occurred (1 hour). The solution was poured onto ice. The precipitate, after being washed and dried, was dissolved in ethanol, treated with carbon and reprecipitated with water. 122 g. of product were recovered. M.P.: 200-201 C.

The material was then suspended in acetonitrile. 10 g. of product were recovered. M.P.: 205-210 C. Yield: 67%.

The results obtained with these couplers were compared with those obtained by the two following materials, which differ substantially by virtue of an amido rather than an ureido group:

C O OH C. PREPARATION OF S-BENZOYLAMINO- INDAZOLONE (COMPOUND 3) (a) Preparation of 2-tosy1-5-benzoylamino-indazolone 10.6 g. (3.5/100 mol) of 2-tosyl-S-amino-indazolone were dissolved in 225 ml. of dry pyridine in a flask, provided with stirrer, reflux condenser and dropping funnel. 4.9 g. (3.5/100 mol) of benzoyl chloride dissolved in 60 ml. of dry dioxane, were added dropwise. The mass was slowly heated and the internal temperature was brought to 100 C. After standing for 1 hour, the solution was poured into ice water and hydrochloric acid. A precipitate was thus obtained, which was collected and dried. 13.7 g. of product were obtained having a MP. of 213-216 C. This material by crystallization from acetic acid gave 7.5 g. of final product. M.P.: 222-223 C. Yield: 52%.

(b) Preparation of 5-benzoylamino-indazolone (Compound 3) 10.2 g. (1/ 400 mol) of 2-tosyl-5-benzoyl-amino indazolone were added to ml. of 96% sulfuric acid, d o =1.84. The mixture was left standing for 10 .minutes at 75 C., obtaining a solution which was poured onto ice. The precipitate was filtered off and washed plentifully with water. The product was suspended in ethanol.

5.7 g. of final product were recovered. M.P.: 300301 C. Yield: 91-92%.

D. PREPARATION OF 5 [3 (3" STEAROYL- AMINO 5" CARBOXY) ANILINO SULFO- NYL] BENZOYL AMINO INDAZOLONE (COMPOUND 4) (a) Preparation of the Z-tosyl derivative 12.12 g. (4/100 mol) of 2-tosyl-S-amino-indazolone were placed in a flask, provided with stirrer, reflux condenser and dropping funnel, together with 180 ml. of dry dioxane. At room temperature, 9.56 g. (4/100 mol) of m-chlorosulfo-benzoyl chloride dissolved in 30 ml. of dry dioxane were added. The solution was refluxed for 1 hour. In another flask, provided with reflux condenser, stirrer and dropping funnel, 15.05 g. (3.6/100 mol) of 3-amino-5-stearoylamino-benzoic acid, 6.4 g. (4/ 100 mol) of dry pyridine and ml. of dry dioxane were placed.

The whole was refluxed and the boiling solution previously prepared was added dropwise to the refluxed solution. Then refluxing was continued for 1 hour and the solution was poured onto ice water and hydrochloric acid. 31 g. of a material having a MP. of l62-170 C. were recovered. The latter was crystallized from acetonitrile.

24.4 g. of final product were recovered. M.P.: 162- C. Yield: 67-68%.

(b) Preparation of 5-[3'-(3-stearoylamin0-5"-carboxy)- anilino-sulfonyl]-benzoylamino-indazolone (Compound 20 g. (2.252/100 mol) of the tosyl-derivative were slowly added to ml. of 96% sulfuric acid,

The internal temperature rose to 70 C. After completion of the addition this temperature was maintained for 10-15 minutes, then the mass was poured onto ice. 12.2 g. of a material having a MP. of 213-225 C. were recovered. This material, when suspended in acetonitrile, produced 10 g. of final product.

M.P.: 220232 C. (softens at C.) Yield: 63%.

EXAMPLE 1 A sample of a silver halide emulsion photographic material was exposed and then developed in a chromogenic developer having the following formulation:

G. Sodium carbonate 10 N,N-diethyl-p-phenylene diamine sulfate 8 Coupler (1) dissolved in 10 ml. of ethanol 1 Water to make 1000 ml.

The developed material was washed, then processed in a bleaching bath, washed, fixed, again Washed and dried.

A magenta-colored image was thus obtained by the formation of a dye having a main absorption peak of about 528-530 mg.

EXAMPLE 2 By substituting in the chromogenic developer of the Example 1 for the coupler (1) an equal amount of the coupler (3,), a magenta-colored image was obtained by the formation of a dye having a main absorption peak of about 530-532 mg.

EXAMPLE 3 12 g. of the coupler (2). were brought into solution with 20 ml. of methanol, 20 ml. of a 2 N NaOH solution and 250 ml. of water. This solution was added to one kilogram of silver halide photographic emulsion, which was then spread onto a support. The photosensitive material thus obtained was exposed and then developed by means of a diethyl-p-phenylene diamine chromogenic developer. After bleaching and fixing treatment, a magenta-colored image having a main absorption peak of about 566568 In was obtained in the exposed areas.

EXAMPLE 4 Dyes derived from couplers Decrease in color density after exposure in iadometer after (percent)- The present The prior invention art 7 hours 30 hours 30 hours From an examination of this illustrative data it can be seen that the light storageability is significantly better for the dyes obtained from the ureido indazolone couplers of this invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A photographic processing solution useful for chromo genic development by coupling with a para-phenylene diamine developer, said processing solution containing a ureido indazolone as color coupler.

2.' The photographic processing solution of claim 1 in which said ureido indazolone has the formula wherein R is hydrogen, alkyl, aryl or a heterocyclic radical.

3. A process for producing light stable, color photographic images in a silver halide emulsion layer which comprises the chromogenic development of a dye by coupling with a para-phenylene diamine developer an ureido indazolone.

4. The process of claim 3 in which said ureido indazolone has the formula wherein R is hydrogen, alkyl, aryl or a heterocyclic radical.

References Cited UNITED STATES PATENTS 2,964,402 12/1960 Jennen et al 9656.5 3,393,071 7/ 1968 Monbaliu et al 96--56.5

I. TRAVIS BROWN, Primary Examiner 

